Pressure image transfer process



Dec. 12, 1961 'r. ABBOTT ETAL 3,012,885

PRESSURE IMAGE TRANSFER PROCESS Filed Dec. 3, 1956 2 Sheets-Sheet 1CONTAIN/N6 COUPLER SILVER HAL/DE EMULSION K DISPERSION DYE AND COUPLERSOLVENT TRANSFERRED I4- Thomas LAbboli' James II. Shepler Henry 6. YuizylagitlTORf BY (2. M

ATTORNEYS Dec. 12, 1961 T. ABBOTT ETAL 3,012,885

PRESSURE IMAGE TRANSFER PROCESS Filed Dec. 3, 1956 2 Sheets-Sheet 2--OYE IN COUPLER SOLVENT l '-SILVER HAL/DE EMULSION 20 A C ONTA/N/NGDEVELOPER IN OF GEL TIN l IMAGE EXPOSURE S T A UNTAN/VED AREAS REMOVEDThomas LAbboH James HS'he nler Henry (I. Yutz y I IN VENTOR BYJZMA'I'TORNETYS PRESSURE This invention relates to photography andparticularly to a process of transferring a photographic image bypressure.

Photographic images have been transferred from a printing original to ablank receiver in various Ways, such as imbibition of dye, diffusion ofsalts or other image components, and transfer of image colloid. Whilepressure of the original against the receiver is involved to some extentin all of these methods, pressure has not been employed to squeeze orpress the image out of the original into the receiver.

It is therefore an object of the present invention to provide a novelpressure image transfer method. A further object is to provide a methodfor transferring a colored image from a photographic emulsion layer to areceiving sheet. Other objects will appear from the followingdescription of our invention.

These objects are accomplished according to our invention by firstforming a dye image in a hydrophilic colloid layer of a photographicelement having a silver halide emulsion layer, the colloid layercontaining a dispersion of a solution of color-forming compound orcoupler in an organic crystalloidal solvent for the coupler and the dyeformed from it, having a boiling point above about 175 C., and thenpressing the colloid layer containing the image into contact with anoil-absorbent receiving sheet with sufiicient pressure to cause theorganic solvent and dye image to transfer to the receiving sheet.

In the accompanying drawing,

FIG. 1 illustrates the steps in our process by means of sectional viewsof the film being treated, and

FIG. 2 illustrates a modification of our process also by means ofsectional views of the film at successive stages in the process.

The material employed in the method of our invention is a hydrophiliccolloid layer such as gelatin, coated on any suitable flexible supportsuch as cellulose ester, paper or synthetic resin, containing in thegelatin or other hydrop'nilic colloid a dispersion of a solution of acouler or dye in a solvent for the coupler or dye, and for the dyeformed from the coupler.

The coupler is one which is capable of coupling with the oxidationproduct of a primary aromatic amino developing agent on photographicdevelopment, suitable couplers being disclosed in Jelley and Vittum U.S.Patent 2,322,027, Loria et al. US. Patent 2,600,788, McCrossen et al.US. patent application Serial No. 476,159, Thirtle and Weissberger US.patent application Serial No. 550,- 755 and Glass et al. US. Patent2,521,908.v Since the couplers of the latter patent are colored, theymay also be considered dyes.

The solvent in which the coupler or dye is dissolved is an organiccrystall'oidal solvent for the coupler or dye, and for the dye formedfrom the coupler, having a boiling point above about 175 C. Suitablesolvents include di-n-butyl phthalate, diethyl lauramide, tricresylphosphate, and other coupler solvents disclosed; in Ielley and VitturnUS. Patent 2,322,027.

The coupler or dye is first dissolved in the organic solvent in anysuitable ratio, such as 1 part of coupler or dye in from. 1 to parts oforganic solvent. More or less coupler may, however, be employed. Thesolution is then dispersedin gelatin or other hydrophilic atent3,012,835 Patented Dee 12, 1961 2 4 colloid, and this may be coated onthe support as such, or mixed with a silver halide emulsion and coated.Two or more coatings of diiferent couplers may be superposed on thesupport, or two or more dispersions of different couplers may be mixedin a single layer.

In the layer just described, the ratio of gelatin (or other hydrophiliccolloid) to organic solvent is critical. This ratio should be one partof gelatin to from 1 to 5 parts of organic solvent, by weight. Since ourprocess depends upon squeezing or pressing the solution of coupler ordye from the gelatin layer onto .a receiving sheet, the amount ofsolution'should be high in relation to the amount of gelatin in thelayer. In the usual photographic layer containing a coupler dispersion,there is much less coupler and solvent solution in relation to thegelatin, than in the material which We use.

The manner in which our process produces an'image will now be described,referring to the accompanying drawing as required.

As shown in FIG. 1, a support 10 is coated with a gelatino-silverhalidelayer 11 containing a dispersion of particles 12 of colorless couplerdissolved in the organic solvent. This layer is given an image exposureand is developed in a primary aromatic amino developingsolutionto'produce a developed ,dye image where thelayer was exposed, asshown by the solid dots 13 in the second stage of FIG. 1. The layer neednot be fixed, but is preferably wiped dry with a squeegee, and is thenplaced face down on an absorbent receiving sheet 14 on a flat surface. Aheavy roller 15 is then used to roll the two sheets tightly together.This presses the solvent and dye image 13 onto the receiving sheet 14,as shown at 16, leaving dye particles in the sheet 14 as a reproductionof the original colored image 13. Since not all of the original image isremoved by the transfer, successive transfers may be made from theoriginal to successive receiving sheets.

Another modification of our invention is shown in FIG. 2 of the drawing.In this modification, a support 17 of cellulose ester, paper orsynthetic resin is coated with a gelatin layer 18 containing adispersion 19 of a solution of dye in organic solvent. The layer 18 istherefore uniformly colored by the dye dispersion. This layer isovercoated with a layer 20 of silver halide in soft gelatin containing atanning developing agent. This sensitive layer is of the type describedin Yutzy and Yackel US. Patent 2,596,75

Upon exposure of this element to a lineor half-tone image anddevelopment as described more fully hereinafter, developed and tannedgelatin areas 21 are produced where the layer 20 was exposed. Softgeladn areas 22 remain in the unexposed areas. The gelatin in theseareas is removed by washing the element with warm water, as shown at 23in the third stage of PEG. 2.

By pressing this element against an absorbent receiving sheet 24 bymeans of roller 15, as shown in the last stage of FIG. 2, gelatin layer18 is forced through the open spaces in layer 18,. causing this layer tocontact the receiving sheet 24 at those areas. The dispersed particles.19 are thereby caused to transfer to the receiving sheet as shown at.25,, resulting in an image in the receiving sheet corresponding to theunexposed portions of the sensitive layer 20.

Our invention will be further explained by reference to the followingspecific examples:

Example 1 This example illustrates a single-layer coating.

A coating was made on cellulose acetate film base at a wetv thickness of.005. inch, of an emulsion prepared as follows;

1 0, cc. of a gelatino-silver chloride emulsion containing Coupler 1grams 5 Di-n-butyl phthalate cc 50 Gelatin, solution cc 100 Alkanol B,5% solution (alkyl naphthalene solulution cc-.. 25

1 2-(2, hdl-n-arnylphenoxyacetamino)4,6 dlchloro5-methyl- 1%1 11 og'rh1rt1e and Weissberger US. application Serial No.

This mixture was passed through a colloid mill before mixing it withsilver halide emulsion. The coating was dried and processed as follows:

The emulsion was exposed to a negative subject by Photo-flood light andprocessed for 30 seconds in a developer of the following composition:

Grams 4-amino-N-ethyl-N-(fi-methanesulfonamidoethyl)-mtoluidinesesquisulfate monohydrate Sodium sulfite (desiccated) 4 Sodiumcarbonate, monohydrate Sodium sulfate 100 Water to 1 liter.

Example 2 This example describes a two-layer coating. A red-sensitiveemulsion layer was made by mixing 10 cc. of a coupler dispersionprepared as in Example 1, i

with 5 cc. of a red-sensitive gelatino-silver chlorobromide emulsioncontaining 0.278 mole of silver halide per liter of emulsion and coatingthe mixture on a cellulose acetate film support.

Over this emulsion there was coated a green-sensitive emulsion made bymixing 10 cc. of a coupler dispersion made as in Example 1 but replacingthe coupler with 1 (2',4',6' trichlorophenyl) 3 [3" (2',4' ditert.amylphenoxyacetamido)benzamido] 5 pyrazolone (US. Patent 2,600,788),with 5 cc. of a green-sensitive gelatino-silver chlorobromide emulsioncontaining 0.314 mole of silver halide per liter of emulsion.

The double coating was dried and exposed separately to a line subjectthrough Wratten No. 61 filter (green) and Wratten No. 29 filter (red).Film was then developed for two minutes in the developer of Example 1and treated for 10 seconds in a stop bath of a saturated solution ofsodium sulfate with the pH adjusted to 3.0 with acetic acid. The surfaceof the coating was then wiped dry with a squeegee and rolled in contactwith double weight photographic paper stock in a clothes wringer.

When the strips were separated there resulted a transferred line imageof magenta and cyan dyes. The receiving sheet was then washed with waterto remove any unreacted developer.

Example 3 The example illustrates a mixed coupler coating. Five grams ofa silver chloride emulsion containing 1 mole of silver chloride perliter of emulsion was mixed with 8 grams of 10% gelatin solution and 20grams of the following coupler dispersion:

Cyan coupler 1 grams 5 Magenta coupler do 10 Yellow coupler 3 d 15Di-n-butyl phthalate cc.. 50 Gelatin, 10% solution cc Alkanol B, 5%solution cc 10 1 2-(adi-tert.-amylphenoxy-nbutyrylamino) 4,6 dichloro-5-methylphenol (Flerke and Chechak U.S. application Serial No. 476,561).

2 Same as magenta coupler of Example 2.

3-benzoylacetamino-4methoxy- (2',4-di-tert.-arnylphenoxy) acetanilide(McCrossen et al. U.S. patent application Serial No. 476,159).

The coupler dispersion passed through a colloid mill before mixing withthe emulsion, and the mixture was coated at a wet thickness of .002 inchand dried.

The coating was exposed through a continuous tone step wedge, linenegative, and half-tone positive, respectively. The three exposed stripswere processed for 30 seconds in the developer of Example 1 and thecoating was wiped dry with a squeegee and rolled in contact with adouble weight photographic paper stock in a clothes wringer.

When the strips were separated, there resulted a neutral tonetransferred line image with very high sharpness and clean background,smooth continuous tone image from the continuous tone step wedge but onewhich was not equal in tone because of unequal coupling rates of thecouplers from the line negative, and a half-tone image with very sharpdots from the half-tone positive.

Example 4 This example describes transferring a dye dispersion through agelatin matrix.

A cellulose ester film base was coated with a dye dispersion made asfollows:

100 cc. of a 10% aqueous gelatin solution was mixed with a solution of10 grams of 1-hydroxy-4-phenylazo-4'-(p-tert.-butylphenoxy)-2-naphthanilide in 60 cc. of diethyl lauramide,and 15 cc. of 5% aqueous Alkanol B solution with enough water to make200 grams of solution. This mixture was milled five times in a colloidmill and one part by weight of the dispersion was added to one part byweight of a 10% aqueous gelatin solution. After stirring thoroughly, themixture was coated on the support giving, when dried, a coatingcontaining .720 gram of gelatin, .240 gram of dye and 1.44 grams ofdiethyl lauramide per square foot.

A second layer of silver chloride emulsion containing tanning developingagent was coated on the gelatin layer containing the dye dispersion.This emulsion was prepared from a gelatino-silver chloride emulsioncontaining one mole of silver chloride in 3600 grams of emulsion, andwas mixed with the following ingredients:

The dispersion of 4-pheny1 catechol which is the tanning developingagent was made by adding a solution of 50 grams of 4-phenyl catechol in50 cc. of tricresyl phosphate to a mixture of 500 cc. of 10% gelatinsolution and 15 cc. of 15% saponin solution and adding water to give 700grams total mixture. This mixture was milled five times in a colloidmill before adding it tothe emulsion.

The second layer was coated over the first and dried. The emulsion wasexposed to a high contrast positive transparency and processed for 20seconds in an aqueous clothes wringer. After three passes through thewringer,

the untanned gelatin was removed from the unexposed portions of theemulsion and subsequent transfers could then be made to separate sheetsof paper to produce a dye image by squeezing dye through the areas wherethe unhardened gelatin had been removed. The same result occurred withthe matrix developed at the different temperatures stated above, but atthe higher temperatures, the unexposed gelatin was more quickly removed.

Numerous variations may, of course, be made in our process withoutdeparting from the scope of our invention. For example, the ratio ofcoupler to coupler solvent, the ratio of gelatin to coupler solvent, thetemperature at the time of transfer, and the transfer pressure, may allbe varied over a wide range. These variations are illustrated by thetests now to be described.

A series of coatings was made as in Example 1, using plain gelatininstead of silver halide emulsion, and employing the coupler2-(a-di-tert.-amylphenoxy-n-butyrylamino)-4,6-dichloro-5-methyl phenol(Fierke and Chechak U.S. patent application Serial No. 476,561, now US.Patent No. 2,801,171). The coatings were so designed that each contained0.540 gram of gelatin (calculated as dry gelatin) and 0.345 gram ofcoupler per square foot of film base on which the dispersions werecoated. The amount of coupler solvent was varied as shown in thefollowing table:

Ratio coupler to coupler solvent Ratio gelatin to coupler solvent Asqueezing device was made so that the transfer pressure could be variedfrom 1 kg. per sq. cm. to 11 kg. per sq. cm. Transfers were then madefrom the various samples to the baryta side of baryta-coated paper,employing various pressures and temperatures. This transferred uncoloredcoupler and coupler solvent to the paper. The paper samples were dippedinto a solution of 2 grams of 2-amino-5-diethylamino toluene and 5 g. ofsodium sulfite per liter of water, and then into an oxidizing solutionof 10 g. of potassium ferricyanide and g. of sodium carbonate per literof water to oxidize the developer and form a uniform dye image wheresuflicient coupler had transferred.

The results with respect to pressure variation at a transfer temperatureof 72 F. and transfer time of 1 minute are shown in the following table.The amount of trans fer is indicated as follows:

0=trace +=medium s +++=highest Coating No. 1 kg. per 2 kg. per 3 kg. per6 kg. per 11 kg. per

sq. cm. sq. cm. sq. cm. sq. cm. sq. em.

None None None None None None 0 0 0 0 0 0 0 0 0 The results with respectto temperature variation at a transfer pressure of 6 kg. per sq. cm. andtransfer time of 1 minute are shown in the following table, the amountof transfer being indicated as before.

Coating N0. F. I F. IIOOQRIHU" 11,125? 15. a 8 2 i .1 niZZI IV Noresults are shown for variation in time of transfer, because variationof time from a fraction of a minute to several minutes made nodifference in the results.

Instead of the coupler solvents described above, it is possible to use ahigh-melting-point hydrocarbon wax. In this case it is necessary toapply heat as well as pressure to obtain an image transfer.

-It will be understood that the examples and modifications describedabove are illustrative only, and that our invention is to be taken aslimited only by the scope of the appended claims.

What we claim is:

l. The method of forming a dye image in an oilabsorbent receiving sheetby transfer, which comprises forming a coupler compound image byexposure and color development with a primary aromatic amino developingagent, in a light-sensive element including a layer of hydrophiliccolloid containing a dispersion of a coupler compound capable ofreacting with the oxidation product of a primary aromatic aminodeveloping agent to form a dye, said coupler compound being dissolved inan organic crystalloidal solvent for the coupler and for the dye formedtherefrom and having a boiling point above about (1., the ratio ofhydrophilic colloid to organic solvent being between about 1 to 1 and 1to 5, and while retaining said hydrophilic colloid in said layer,pressing said element into contact with an oil-absorbent receiving sheetwith sufficient pressure to cause said organic solvent and couplercompound image to transfer to said receiving sheet.

2. The method of transferring a dye image from a photographic emulsionlayer to an oil-absorbent receiving sheet, which comprises forming a dyeimage by exposure and color development with a primary aromatic aminodeveloping agent, in a gelatino-silver halide emulsion layer containinga dispersion of a color coupler capable of reacting with the oxidationproduct of a primary aromatic amino developing agent in an organiccrystalloidal solvent having a boiling point above about 175 C., theratio of gelatin to organic solvent being between about 1 to 1 and 1 to5, and while retaining said gelatin in said layer, pressing said layerinto contact with an oilabsorbent receiving sheet with sufficientpressure to cause said organic solvent and dye image to transfer to saidreceiving sheet.

3. The method of transferring a dye image from a photographic emulsionlayer to an oil-absorbent receiving sheet, which comprises forming a dyeimage by exposure and color development with a primary aromatic aminodeveloping agent, in a gelatino-silver halide emulsion layer containinga dispersion of di-n-butyl phthalate having dissolved therein a colorcoupler capable of reacting with the oxidation product of a primaryaromatic amino developing agent, the ratio of gelatin to di-n-butylphthalate being between 1 to 1 and 1 to 5, and while retaining saidgelatin in said layer, pressing said layer into contact with anoil-absorbent receiving sheet with a pressure of 1 to 11 kilograms persquare meter to cause said di-nbutyl phthalate and dye image to transferto said receiving sheet.

4. The method of transferring a dye image from a developing agent, in agelatino-silver halide emulsion layer containing a dispersion ofdi-n-buty1 phthalate having dissolved therein2-(2,4-di-n-amylphenoxyacetamino)- 4,6-dichloro-5-methylphenol, theratio of gelatin to di-nbutyl phthalate being approximately 1 to 5, andwhile 5 retaining said gelatin in said layer, pressing said layer intocontact with an oil-absorbent receiving sheet with a pressure of 1 to 11kilograms per square meter to cause said di-n-butyl phthalate and dyeimage to transfer to said 10 receiving .sheet.

References Cited in the file of this patent UNITED STATES PATENTSConnolly May 14, 1907 Martinez Nov. 14, 1933 Williams Nov. 20, 1934Jelley et al. June 15, 1943 Land Feb. 27, 1951 Murray July 24, 1956Godowsky et a1. Apr. 2, 1957 Illingsworth et a1. Sept. 16, 1958

1. THE METHOD OF FORMING A DYE IMAGE IN AN OILABSORBENT RECEIVING SHEETBY TRANSFER, WHICH COMPRISES FORMING A COUPLER COMPOUND IMAGE BYEXPOSURE AND COLOR DEVELOPMENT WITH A PRIMARY AROMATIC AMINO DEVELOPINGAGENT, IN A LIGHT-SENSIVE ELEMENT INCLUDING A LAYER OF HYDROPHILICCOLLOID CONTAINING A DISPERSION OF A COUPLER COMPOUND CAPABLE OFREACTING WITH THE OXIDATION PRODUCT OF A PRIMARY AROMATIC AMOINODEVELOPING AGENT TO FROM A DYE SAID COUPLER COMPOUND BEING DISSOLVED INAN ORGANIC CRYSTALLOIDAL SOLVENT FOR THE COUPLER AND FOR THE DYE FORMEDTHEREFORM AND HAVING A BOILING POINT ABOVE ABOUT 175*C., THE RATIO OFHYDROPHILIC COLLOID TO ORGANIC SOLVENT BEING BETWEEN ABOUT 1 TO 1 AND 1TO 5, AND WHILE RETAINING SAID HYDROPHILIC COLLIOD TO PRESSING SAIDELEMENT INTO CONTACT WITH AN OIL-ABSORBENT RECEIVING SHEET WITHSUFFICIENT PRESSURE TO CAUSE SAID ORGANIC SOLVENT AND COUPLER COMPOUNDIMAGE TO TRANSFER TO SAID RECEIVING SHEET.